The invention relates to a pressure unit for pressurizing a belt shaft in a seat belt system comprising a screw for fastening the pressure unit to a frame of the seat belt system, wherein the screw includes a screw head and a screw shank and wherein the pressure unit comprises a fastening portion having a screw hole for inserting the screw shank. Further, the invention relates to an end fitting comprising said pressure unit, with a tensioner drive being preferably provided which is adapted to drive the belt shaft in a winding direction.
Belt tensioners for seat belt systems are generally known from automotive engineering. In so called end fitting tensioners in the case of activation of the belt tensioner the actually fixed end of webbing usually connected to the seat frame or the vehicle body is tightened to provide for tensioning of the entire webbing. In prior art both linearly operating and rotational end fitting tensioners are described. In the case of the rotational end fitting tensioners the webbing end is connected to a belt shaft which is driven upon activation of the belt tensioner so as to wind webbing onto the belt shaft.
For mounting the seat belt system especially with reference to end fitting tensioners increasingly there is wanted a process in which the webbing end is not fastened to the belt tensioner before the belt tensioner has been mounted on the vehicle body or on the seat frame.
In order to enable such subsequent fastening of the webbing with minimum assembly effort, DE 10 2011 117 052 A1 suggests an end fitting tensioner for a seat belt system comprising a frame, a belt shaft being rotatably supported in the frame about an axis as well as a belt shaft insertion element to which one end of webbing is fastened, wherein the belt shaft includes a recess for receiving the belt shaft insertion element and wherein the belt shaft insertion element can be inserted substantially radially into the recess. Moreover, there is provided a generic pressure unit which in the completely mounted state of the end fitting pressurizes the belt shaft into its locking position and thus ensures high functional safety of the end fitting tensioner.